So my control cards were looking a bit natty, and I wanted some new ones. But I really didn’t want to buy the the typical thin ones on offer- they don’t hold up and I write on them too so I had been using some Japanese adidas ones that are more like credit cards in stiffness. And I had seen those wicked amour reflective ones, but at $12 a set I thought them a bit overpriced. So I decided to try some reflective tape (you know, the kind you put on a truck or sign to make it more visible at night) applied to 1/16” Lexan. After a few iterations i settled on 3m conspicuity tape- I think the colors are perfect. Then I tried just putting the tape back to back on itself without any stiffening layer, found that they are great that way too. The one on the left is the same size as the ones from proreferee, which are kinda oversized. It’s not the cheapest thing in the world but now I have cards that I’m happy with and can make them whatever size I want.
I have write on stickers that let you use a pencil or ballpoint. The surface is glossy and a sharpie works well (I don’t use a sharpie since it doesn’t do well when it’s raining).